A.2.5:4.7 - State-Machine and Change Lenses

Use statecharts or state machines when mutually exclusive configurations, orthogonal regions, guarded changes, or event handling improve the subject-domain model. The notation describes possible configurations and changes; it does not replace the direct relation occurrence.

A change arrow represents a proposed or observed change in predicate truth; it is not the world-side change by form. Recover the exact changed object or relation, then use the direct pattern governing that change. Use the Method description for any prescribed Method order.

When the model needs continuous coordinates rather than discrete labels, use A.19 for the characteristic space and let the by-value state predicate select a region, band, ordering condition, or other exact condition. Measurement and evaluation stay with C.16 and their direct patterns.